The present invention relates to a liquid crystal module to be installed in an electronic device such as a television, a personal computer, or the like. More particularly, the present invention relates to a liquid crystal module which is capable of lowering costs and improving brightness at both left and right side portions of a display surface by attaching a cover made of a light reflection sheet which is inexpensive and superior in light reflectivity, instead of a lamp frame made of synthetic resin, with an appropriate fixing structure for covering and concealing end portions of a cold cathode tube.
A related-art liquid crystal module has a fixing structure in which a light reflective sheet and a cold cathode tube are disposed in a rear frame, lamp frames made of synthetic resin are arranged inside left and right side plates of the rear frame for covering and concealing end portions of the cold cathode tube, left and right edge portions of an optical sheet are inserted into a groove portion of the lamp frames, upper and lower edge portions of the optical sheet are mounted on upper and lower side plates of the rear frame and pressed by cell guides, and four circumferential edges of a liquid crystal panel are mounted on the lamp frames and cell guides and enclosed and fixed by a bezel.
The lamp frame is used in the related-art liquid crystal module for covering and concealing end portions of the cold cathode tube to prevent variation in brightness at both left and right side portions of a display surface of the liquid crystal panel and for reflecting light from the cold cathode tube to prevent deterioration in brightness at both left and right side portions of the display surface. The lamp frame is made of white synthetic resin having good light reflectivity and is formed by injection molding.
Patent Document 1 disclose a display device in which left and right light reflective sheets are disposed inside left and right side plates of a box-shaped fixing member to cover and conceal end portions of a cold cathode tube, and a plurality of protrusions formed at lower end portions of the left and right light reflective sheets are adhered to, by an adhesive or double-sided tape, a plurality of uprising pieces at both left and right end portions of the light reflective sheet which is provided at a bottom surface of the fixing member. Patent Document 1 also discloses a display device in which tip ends of the protrusions formed at the lower end portions of the left and right light reflective sheets are inserted into a plurality of grooves formed in left and right edge portions of the light reflective sheet which is provided at the bottom surface of the fixing member.
Patent Document 1: JP-A-2005-322645
In the related-art liquid crystal module in which the lamp frame made of white synthetic resin is mounted, since such lamp frame is expensive, it is difficult to satisfactorily fulfill the requirement for lowering the manufacturing costs of recent liquid crystal televisions. Although the lamp frame made of the white synthetic resin has good light reflectivity, the light reflectivity of the lamp frame is lower than that of the light reflective sheet. Accordingly, there is room for further improvement in the brightness at both left and right side portions of the display surface of liquid crystal panel in the related-art liquid crystal module.
The display device disclosed in Patent Document 1 in which the protrusions formed at the lower end portions of the left and right light reflective sheets are adhered to, by the adhesive or the double-sided tape, the uprising pieces at the left and right end portions of the light reflective sheet which is provided at the bottom surface of the fixing member, or in which the tip ends of the protrusions formed at the lower end portions of the left and right light reflective sheets are inserted into the grooves formed in the left and right edge portions of the light reflective sheet which is provided at the bottom surface of the fixing member, has a problem in that assembly workability is not good. In particular, the latter device in which the tip ends of the protrusion are inserted into the grooves of the light reflective sheet has a problem in that the left and right light reflective sheets are easily detached from the light reflective sheet in the bottom surface. In addition, in the display device disclosed in Patent Document 1, the upper edges of the left and right light reflective sheets are merely overlapped with the upper surfaces of the left and right side plates of the fixing member without using special fixing means. Accordingly, the upper edges of the left and right light reflective sheets may be easily detached from the left and right side plates of the fixing member.